Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number TRD-1220 found under Bearing Washer Thru by Koyo Bearings Usa Llc. The National Stock Number assigned to this part is 3120009355729, and the Federal Supply Class is 3120 Bearings Plain Unmounted. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like TRD-1220.